Sorry, perhaps I gave the wrong line number; the print statement should be in the second section:
elif PLATFORM == "osx":
# lp -d <queue name> <name of document>
# lp <name of document> will send to default printer(?)
if QUEUE is not False:
subprocess.call("lp -d " + QUEUE + " " + vw_filename)
else:
print(vw_filename)
subprocess.call("lp " + vw_filename)